Japan's Vice Foreign Minister Masahisa Sato says Seoul’s removal of Tokyo from a list of nations receiving preferential treatment in trade would be violating World Trade Organization rules if it was retaliating against Japan's export control measures. 

Sato made the remark on Twitter on Monday, quoting a report on Seoul's latest move. 

The vice minister said that he will look into details to find out why South Korea took the step, adding the measure is unlikely to have substantial impact on Japan as there are few strategic materials imported from South Korea. 

Japan's Kyodo News quoted a senior Foreign Ministry official in Tokyo as saying that Japan will not overreact. The report said Japan is likely to consider its responses after monitoring the situation ahead of Liberation Day in Korea on Thursday.